<template>
    <div class="helper">
        <span class="left">{{unFinishedTodoLength}} items left</span>
        <span class="tabs">
            <span v-for="state in states" :key="state" :class="[state,filter ===state?'actived': '']" @click="toggleFilter(state)">
                {{state}}
            </span>
        </span>
        <span class="clear" @click="clearAllCompleted">clear completed</span>
    </div>
</template>

<script>
    export default {
      props: {
        filter: {
          type: String,
          required: true
        },
        todos: {
          type: Array,
          required: true
        }
      },
      computed: {
        unFinishedTodoLength () {
          return this.todos.filter(todo => !todo.completed).length
        }
      },
      data () {
        return {
          states: ['all', 'active', 'completed']
        }
      },
      methods: {
        toggleFilter (state) {
          this.$emit('toggle', state)
        },
        clearAllCompleted () {
          this.$emit('clearAll')
        }

      }
    }
</script>


<style lang="stylus" scoped>
.helper{
  font-weight 100
  display flex
  justify-content space-between
  padding 5px 0
  line-height 30px
  background-color #fff
  font-size 14px
  font-smoothing: antialiased
}
.left, .clear, .tabs{
  padding 0 10px
  box-sizing border-box
}
.left, .clear{
  width 150px
}
.left{
  text-align left
}
.clear{
  text-align right
  cursor pointer
}
.tabs{
  width 200px
  display flex
  justify-content space-around
  * {
    display inline-block
    padding 0 10px
    cursor pointer
    border 1px solid rgba(175,47,47,0)
    &.actived{
      border-color rgba(175,47,47,0.4)
      border-radius 5px
    }
  }
}
</style>


